Abhijit Guha Solutions for Chapter: Time, Speed and Distance, Exercise 1: Practice Problems Level 1

Wheels of diameters $7 \mathrm{cm}$ and $14 \mathrm{cm}$ start rolling simultaneously from X and Y, which are $1,980 \mathrm{cm}$ apart towards each other in opposite directions. Both of them make the same number of revolutions per second. If both of them meet after $10$ seconds, the speed of the smaller wheel is

Three persons start walking together and their steps measure $40 \mathrm{cm}$, $42 \mathrm{cm}$ and $45 \mathrm{cm}$, respectively. What is the minimum distance each should walk so that each can cover the same distance in complete steps?

A hare starts running with initial speed of $40 \mathrm{km}/\mathrm{h}$ with its speed increasing every hour by $5 \mathrm{km}/\mathrm{h}$. How many hours will it take to cover $385 \mathrm{km}$?

A thief spots a policeman $100 \mathrm{m}$ away and takes to his heels if the policeman gives a chase immediately, then how far would the thief have run before he is caught? The speeds of the policeman and thief are $10 \mathrm{km}/\mathrm{h}$ and $8 \mathrm{km}/\mathrm{h}$.

A thief goes away at $8 \mathrm{p}.\mathrm{m}.$ with a Maruti car at a speed of $40 \mathrm{km}/\mathrm{h}$. The theft has been discovered after half an hour and the owner sets off in another car at $50 \mathrm{km}/\mathrm{h}$. When will the owner catch the thief from the start?

The distance between two places A and B is $55 \mathrm{km}$. Two horsemen move from A and B towards each other at the speeds of $12 \mathrm{km}/\mathrm{h}$ and $10 \mathrm{km}/\mathrm{h}$, respectively. After what time will they be $11 \mathrm{km}$ apart?

By increasing the speed of the bus by $10 \mathrm{km}/\mathrm{h}$, the time of journey for $72 \mathrm{km}$ is reduced by $36$ minutes. What was the original speed of the bus?

The distance between two stations Dhanbad and Varanasi is $550 \mathrm{km}$. A train starts at $2 \mathrm{p}.\mathrm{m}.$ from Dhanbad and moves towards Varanasi at average speed of $50 \mathrm{km}/\mathrm{h}$. Another train starts at $3 \mathrm{p}.\mathrm{m}.$ Varanasi at average speed of $70 \mathrm{km}/\mathrm{h}$. How far from Dhanbad will they meet?